Means for removing dust from gases.



PATENTED JULY 4, 1905.

J. SHIELDS. MEANS FOR REMOVING DUST FROM GASES.

APPLICATION FILED AUG. 22,1904.

NITED STATES Patented July 4:, 19C 5.

MEANS FOR REMOVING DUST FROM GASES.

SPECIFICATION forming part of Letters Patent No. 793,745, dated July 4,1905.

Application filed August 22, 1904. Serial No. 221,787.

To all whmn it may concern:

Be it known that I, J OI-IN SHIELDS, doctor of science, a subject of theKing of Great Britain, residing at 4 Stanley Gardens, Willcsden Green,in the county of Middlesex, England, have invented certain new anduseful Improved Means forRemoving Dust from Gases, of which thefollowing is a specification.

According to this invention I conduct the dusty gases beneath or intothe midst of a constantly-replenished heap of any suitable porous orgranular material and allow the gases to pass upward through the heap,and so escape. The filtering material collects the dust and is graduallydrawn away from the bottom of the heap, the top of which is constantlyreplenished with fresh material. The gases thus encounter cleaner andcleaner material as they rise. Such a filter is especially useful in thetreatment of the gases issuing from pyritesburners, but may be used tocleanse any other gases, as desired.

The filtering material may be coke, sand, crushed quartz, granulated orcrushed slag, pumice or volcanic stone, or the like, and the materialwhich is removed from the bottom of the heap may be cleaned and raisedand delivered while still hot onto the top of the heap. I employ a heapapproximately of the shape of two cones placed base to base, such as Ihave illustrated in the drawings, Figure 1 being a vertical, and Fig. 2a horizontal, section.

a is a chamber the lower portion of which is of approximately conicalshape.

7) is the filtering material.

The gases are conducted into the heap by a pipe 0, having adownwardly-projecting outlet-orifice c, situated beneath a horizontaldisk (Z, supported by the pipe cand girders c, which disk creates acavity in the middle of the heap. The material is continuously drawnaway from the bottom of the chamber by a screw conveyer f and may beraised by an elevator g to a pneumatic or other separator 11., where thedust is removed and passes away by the chute while the cleaned materialfalls through a chute 7 onto the top of the heap. The gases pass upthrough the upper portion of the heap, meeting cleaner material as theyrise, and finally escape by the outlet Z. The large exposed uppersurface of the top of the heap, through which the filtered gascan passaway into the space at the top of the chamber, insures that the velocityof the escaping gases shall be but small, so that very efiicientfiltration is insured, and dry in place of moistened material may beused for the filtering. If desired, the height of the chamber above thedisk may be increased and the lnaterial delivered onto the top of theheap in such a way that'the thickness of material through which thegases have to pass may be varied at pleasure.

What I claim is .1. In a filter for removing dust from gases, thecombination of a closed chamber, the lower portion of which tapersdownward to an outlet orifice, an opening at the top through whichgranular material is always free to drop down into the chamber, a moundof granular material resting in and supported by the tapering lowerportion of the chamber and having a conical upper surface, the slopingsides of which extend to the opening at the top so that a space is leftbetween this upper sloping surface and the top of the chamber, an outletfrom this space for filtered gases to pass away, means for introducinggases to be filtered into the body of the mound of granular material,means for drawing oif granular material from the orifice at the bottom,means for cleansing the dusty material withdrawn from the heap and meansfor delivering the cleansed material to the top of the heap. l

2. In a filter for removing dust from gases, the combination of a closedchamber, the lower portion of which tapers downward to anoutlet-orifice, an opening at the top through which granular material isalways free to drop down into the chamber, a mound of granular materialraised in and supported by the tapering lower portion of the chamber andhaving a conical upper surface, the sloping sides of means for drawingoff granular material from Which extend to the opening at the top sothat the orifice at the bottom.

a space is left between this upper sloping surface and the top of thechamber, an outlet from JOHN bHIELDS' this space for filtered gases topass away, means Witnesses: for introducing gases to be filtered intothe ALFRED NUTTING, body of the mound of granular material and R. T.WILLIAMS.

